If..then..elseif..else..end if

The if..then control statement is a script selection construct forcing the script execution to follow different paths depending on one or several logical conditions.

See: if - script and chart function (script and chart function)

Syntax:  

If  condition then

  [ statements ]

{ elseif condition then

  [ statements ] }

[ else

  [ statements ] ]

end if

 

Since the if..then statement is a control statement and as such is ended with either a semicolon or end-of-line, each of its four possible clauses (if..then, elseif..then, else and end if) must not cross a line boundary.

Arguments:  

Example 1:  

if a=1 then

LOAD * from abc.csv;

SQL SELECT e, f, g from tab1;

end if

Example 2:  

if a=1 then; drop table xyz; end if;

Example 3:  

if x>0 then

LOAD * from pos.csv;

elseif x<0 then

LOAD * from neg.csv;

else

LOAD * from zero.txt;

end if